1. Field
The present invention relates generally to temperature controlled containers, and more particularly, to a portable temperature controlled container.
2. Background
In many portable food vending applications, the use of a portable temperature controlled container is necessary for keeping the product to be dispensed at a particular temperature. For example, in vending applications involving the dispensing of a frozen dessert such as the “soft-serve” variety of soft ice cream, it would be preferable if the ice cream is kept at a temperature that is within a specific range of temperatures. If the ice cream is not kept cold enough, then it will melt. Conversely, if the ice cream is kept at a temperature that is too low, then the ice cream may be too hard to dispense. In other examples, it is desirable that liquids such as beer are cooled and maintained around a certain temperature. It may also be preferable that the food or liquid to be dispensed is to be kept at a temperature that is higher than the ambient temperature. For example, a roaming vendor at a baseball stadium may desire to sell hot dogs at a temperature that is higher than the ambient temperature. In another example, the foods to be dispensed may be a liquid such as hot chocolate or soup.
Adding to the challenge of maintaining food at a particular temperature, in many cases the type of food to be dispensed will often need to be kept at a temperature that is on ah opposite end of the temperature spectrum from the ambient temperature. Thus, on a cold day, hot or warm foods and liquids are desirable. In contrast, on a warm day, cold or frozen foods and liquids are desirable.
Typically, the foods or liquids to be dispensed are carried by a vendor in an insulated container, with the temperature of the interior of the container being maintained around a particular temperature through the use of a source of cooling or heating. For example, cooling may come from a coolant, such as an ice or dry ice (i.e., frozen carbon dioxide) pack, that is much colder than the item to be cooled. As such, it is a challenge to maintain the temperature of the item to be cooled around the desired range if the item is a food product that needs to be cooled, but not frozen, because the coolant is much colder than the food product needs to be. Thus, it would be preferable if the container were able to maintain the temperature of the items contained therein within a specific range even though the source of cooling is at a temperature that is much lower than the desired temperature. Further, the approach used to cool the contents of the container needs to be compatible with the portability aspect of the application. This eliminates such solutions as refrigeration units due to the weight of these units and the amount of energy they need to operate, even though refrigeration units are capable of being turned off and on to control the amount of cold that is generated.
It may also be preferable that the food to be stored in the container is kept at a temperature that is higher than the ambient temperature. The heat source may be a heat pack that generates heat using a chemical reaction or an electrically powered heater. However, similar to the cooling application, the heat source is typically at a higher temperature than the food needs to be. Thus, it would also be preferable if the system were able to maintain the temperature of the items contained therein within a specific range even though the source of heating is at a temperature that is much higher than the desired temperature.
There is therefore a need in the art for a solution to provide a temperature controlled container that is portable and can dispense food easily.